came with mains multivoltage adapter. for in the kitchen, prefer to keep put away and use small battery. scale is male, battery female. pic is inside of battery recess. pin1 gnd, pin2 +7-10v. connected flat 9v to dc power in socket and scale registered "low battery". so i'm guessing the oem battery has the charging circuitry inside.
was hoping to plug my 9v battery holder to the connector rather than soldering to main pcb. but if i can't source a proper connector, that soldering polarised connectors would be better than using single female 1.2mm female spades if they exist.